Search found 615 matches
- Wed Apr 03, 2019 6:44 pm
- Forum: Cartridge
- Topic: EEPROM mapping for homebrew
- Replies: 9
- Views: 12464
Re: EEPROM mapping for homebrew
My 2 cents: standardizing the mapping (i.e. which address and which I2C bits are connected where) is good, but I think allowing the size to be specified in the header is desirable. It might make sense to pick a single "mode" (i.e. how the address is sent), but from my perspective supporting any of t...
- Thu Mar 28, 2019 5:21 pm
- Forum: Tools
- Topic: BlastEm 0.6.0
- Replies: 15
- Views: 37130
Re: BlastEm 0.6.0
Hello folks, I've released the next version in the 0.6.X series: BlastEm 0.6.2 . The most notable change for developers is that I have fixed a regression in GDB remote debugging support on Linux and other Unix-like systems (Windows was not affected AFAIK). There are also some small accuracy fixes an...
- Mon Feb 11, 2019 6:48 pm
- Forum: Blabla
- Topic: 68000 Arcade systems programming
- Replies: 14
- Views: 20471
Re: 68000 Arcade systems programming
They're not on his site anymore, but Charles MacDonald actually wrote docs describing various Sega Arcade boards and they are archived at various places:
Pre-System 16
System 16B
System 18
System C2
X-Board
System 24
Pre-System 16
System 16B
System 18
System C2
X-Board
System 24
- Sun Jan 27, 2019 3:45 am
- Forum: Tools
- Topic: BlastEm 0.6.0
- Replies: 15
- Views: 37130
Re: BlastEm 0.6.0
Cool. Yeah, that definitely finds the rom.db. It's probably how I built the project, but it doesn't actually show anything when I run a rom. I get a blank screen and the following error: "Failed to open shader file default.v.glsl for reading" Shaders are expected to be in the "sharers" subdirectory...
- Thu Jan 24, 2019 10:00 pm
- Forum: Tools
- Topic: BlastEm 0.6.0
- Replies: 15
- Views: 37130
Re: BlastEm 0.6.0
Sounds good, I'll give it a go later on. BTW, love the debugging modes on this. This should be very handy! Glad you like them. I have pushed some changes to allow for building a more standard filesystem hierarchy friendly binary. If you want to try it out, grab tip from the repo and build with the ...
- Mon Jan 14, 2019 8:47 pm
- Forum: Tools
- Topic: BlastEm 0.6.0
- Replies: 15
- Views: 37130
Re: BlastEm 0.6.0
Installing in Linux is kind of awkward, since it is not looking in standard locations for config files. /etc/, ~ (according to README). The location of blastem.cfg is standard for a per-user config file. It is true that my tarball is a self-contained package rather than something that's designed to...
- Mon Jan 07, 2019 6:30 pm
- Forum: Tools
- Topic: BlastEm 0.6.0
- Replies: 15
- Views: 37130
Re: BlastEm 0.6.0
There's only one little issue for me with it: checkboxes look like they mean the opposite they should, ie. a black checkbox means "enabled", which seems odd. Yeah, the default checkbox style is one of my biggest beefs with Nuklear. I'll have to see if there are any easy tweaks that can make it a bi...
- Sat Jan 05, 2019 9:09 pm
- Forum: Megadrive/Genesis
- Topic: 68K inner workings
- Replies: 6
- Views: 12991
Re: 68K inner workings
Have you had a look at the 68K patents? Looks like you've managed to figure out a lot from the schematic, but the US4325121 patent specifically has a lot of information about how the microcode/nanocode works and includes micro/nanocode listings for a pre-release version of the processor which might ...
- Fri Jan 04, 2019 6:04 pm
- Forum: Tools
- Topic: BlastEm 0.6.0
- Replies: 15
- Views: 37130
Re: BlastEm 0.6.0
v0.6.0 ended up being kind of buggy due to an abbreviated QA cycle. v0.6.1 fixes a number of issues and is now available here
- Tue Jan 01, 2019 8:43 am
- Forum: Tools
- Topic: BlastEm 0.6.0
- Replies: 15
- Views: 37130
BlastEm 0.6.0
I've released a new version of my Gen/MD emulator. Big change this time is a new UI using the Nuklear toolkit. Unlike the old UI, you can actually change almost all config options through the UI rather than editing the config file. Of interest to developers are some improvements to the VDP debug vie...
- Sat Dec 01, 2018 4:13 am
- Forum: Exodus
- Topic: Genesis 68K bus timing
- Replies: 6
- Views: 12691
Re: Genesis 68K bus timing
Here's a small collection of captures of various types of bus interactions. They are in Open Logic Sniffer Project format. Explanations below: direct_color_dma.olp - Capture of the start of 68K->VDP DMA from one of Chilly WIlly's Direct Color DMA samples (note that !CAS and !RAS here refer to VRAM !...
- Fri Nov 30, 2018 6:33 pm
- Forum: Exodus
- Topic: Genesis 68K bus timing
- Replies: 6
- Views: 12691
Re: Genesis 68K bus timing
I am searching hardware level information about the interface with the 68K. Do you know if anybody performed logic analyzer traces showing the timing of the clock and the bus control signals? Yes. 68K clock is always the master clock/7 (unless you count the Teradrive which can also run the CPU at 1...
- Tue Nov 20, 2018 7:30 pm
- Forum: Megadrive/Genesis
- Topic: Looping access from 68K and Z80
- Replies: 25
- Views: 29636
Re: Looping access from 68K and Z80
My breakout boards cam it but sadly the pads for the pins on the chip were just a tad too short. New boards ordered but with the US holiday coming up it’ll be 10-14 days before I get them back. In the meantime, I found a semiconductor seller that had some genesis chips in stock so I picked up a cou...
- Thu Oct 11, 2018 7:12 pm
- Forum: Megadrive/Genesis
- Topic: Bus Arbiter and IO Chip Access
- Replies: 28
- Views: 37809
Re: Bus Arbiter and IO Chip Access
It would be interesting to verify is there are any differences regarding EDCLK between MD VA1 and late rmodels since it seems VA1 (and likely VA0) is using an earlier version of 315-5345 chip (see 315-5339 description here: http://www.tmeeco.eu/SMD/MD1VA1_315-5339.jpg) which does not use VCLK (and ...
- Thu Oct 11, 2018 7:18 am
- Forum: Megadrive/Genesis
- Topic: Bus Arbiter and IO Chip Access
- Replies: 28
- Views: 37809
Re: Bus Arbiter and IO Chip Access
EDCLK: This signal is 0/floating (wasnt a very clean 0) when /SRES, /M3 or /HSYNC are asserted(0). Otherwise it seems to be MCLK/4. (I tested with a 5k signal. Got a 1.25K out. I thought this this should /5, maybe it doesn't like the slow speed?) Does not seem to be affected by anything else. It sh...